Precipitation Observations and Forecasts for Innsbruck
Accumulated 5-8 days precipitation amount for Innsbruck. Data includes GEFS reforecasts (Hamill et al. 2013) and observations from SYNOP station Innsbruck Airport (11120) from 2000-01-01 to 2013-09-17.
data("RainIbk")A data frame with 4977 rows. The first column (rain) are 3 days
accumulated precipitation amount observations, Columns 2-12 (rainfc)
are 5-8 days accumulated precipitation amount forecasts from the individual
ensemble members.
Observations: http://www.ogimet.com/synops.phtml.en
Reforecasts: http://www.esrl.noaa.gov/psd/forecasts/reforecast2/
Hamill TM, Bates GT, Whitaker JS, Murray DR, Fiorino M, Galarneau Jr TJ, Zhu Y, Lapenta W (2013). NOAA's Second-Generation Global Medium-Range Ensemble Reforecast Data Set. Bulletin of the American Meteorological Society, 94(10), 1553-1565.
## Spread skill relationship ##
## load and prepare data
data(RainIbk)
## mean and standard deviation of square root transformed ensemble forecasts
RainIbk$sqrtensmean <-
apply(sqrt(RainIbk[,grep('^rainfc',names(RainIbk))]), 1, mean)
RainIbk$sqrtenssd <-
apply(sqrt(RainIbk[,grep('^rainfc',names(RainIbk))]), 1, sd)
## quintiles of sqrtenssd
sdcat <- cut(RainIbk$sqrtenssd, c(-Inf, quantile(RainIbk$sqrtenssd,
seq(0.2,0.8,0.2)), Inf), labels = c(1:5))
## mean forecast errors for each quintile
m <- NULL
for(i in levels(sdcat)) {
m <- c(m, mean((sqrt(RainIbk$rain)[sdcat == i] -
RainIbk$sqrtensmean[sdcat == i])^2, na.rm = TRUE))
}
## plot
boxplot((sqrt(rain) - sqrtensmean)^2~sdcat, RainIbk,
xlab = "Quintile of ensemble standard deviation",
ylab = "mean squared error", main = "Spread skill relationship")Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.